Aluminum is a metal which has numerous advantages. It is light, can easily be deep-drawn or drop-forged, and conducts heat well. In addition, it is relatively economical. Because of these qualities, it is universally used in industry, especially for producing cooking vessels.
However, it does have drawbacks. First of all, it is relatively soft, so that its surface scratches easily. In domestic applications, aluminum is often coated with a non-stick layer such as polytetrafluoroethylene or with a layer of enamel. However, the lifetime of these coatings is limited because the aluminum is too soft a support.
Moreover, aluminum articles, and in particular cooking vessels, have a tendency to deform easily due to the effect of heat generated, for example, by an electrical hotplate or a gas burner.
In order to overcome this difficulty, it is possible either to increase the thickness of the metal or to apply a stainless steel sheet to the aluminum wall, for example by hot stamping. However, in this case, the manufacturing cost is substantially increased and the thermal conductivity is reduced, which increases the cooking times.
Moreover, aluminum utensils cannot be heated inductively, as this heating method requires the use of vessels made from magnetic metal such as ferritic stainless steel.